BEIJING (AP) World champions Blanka Vlasic and Tero Pitkamaki withdrew their names from an open letter asking China to improve its policies in Tibet and pay more respect to human rights and censorship issues.
The International Campaign for Tibet confirmed Friday that the two gold-medal favorites were among four athletes at the Beijing Games that had requested Sports for Peace - a German initiative supported by the ICB and Amnesty International - remove their names from an online petition.
Discus thrower Gerd Kanter of Estonia and Finnish javelin thrower Teemu Wirkkala were the other athletes.
Croatia's Vlasic, the world champion in high jump, and javelin champion Pitkamaki of Finland were among the 40 athletes competing at the Beijing Games who had originally signed.
"We absolutely respect the decision of the athletes," said Kate Saunders, communications director for ICB. But "if they withdraw their signatures at some point, this is just another example of censorship and a form of repression that surrounds these games."
The letter asked China President Hu Jintao "to respect human rights in China in order to achieve lasting peace and reconciliation" while enabling "a peaceful solution for the issue of Tibet and other conflicts in your country with respect to fundamental principles of human rights." It also called on China to protect freedom of expression, religion and opinion, and put a stop to the death penalty.
Vlasic's father reportedly told Croatian media on Friday that Vlasic didn't remember signing the petition, and he also questioned the authenticity of the signature.
Sports for Peace said all signatures were authentic, with Saunders blaming the current climate of censorship at the games for causing the four U-turns.
"No athlete will be at risk at the games," Saunders said. "The athletes all knew what they signed."
Signatures were collected at a Golden Gala event in Berlin in June with 127 past and present athletes adding their names. Cuba's Dayron Robles, the world record holder in the men's 110-meter hurdles, was the highest-profile athlete alongside Vlasic and Pitkamaki. U.S. track athletes Lolo Jones and Dee Dee Trotter also signed on.
China's policies concerning the people of Tibet and ethnic Muslim groups in the western part of the country have come under question leading into the games.
On Wednesday, four foreign activists for a Free Tibet unfurled banners in front of the Bird's Nest national stadium - the site of Friday's opening ceremony, where Chinese officials have been fearful that athletes would make gestures or show displays of solidarity with Tibet to a potential worldwide television audience of 1 billion people.
The Olympic torch relay was marred during stops in Paris, London and San Francisco as protesters attempted to extinguish the flame and the symbolic run turned aggressive.
Tibet has been an extremely sensitive topic since protests against almost 50 years of Chinese rule turned violent in the region's capital of Lhasa in March. Many Tibetans insist they were an independent nation before communist troops invaded in 1950, while Beijing says the Himalayan region has been part of its territory for centuries.